Structural members such as tower legs and other columns are frequently made of steel or other metal and sometimes of wood. These conventional materials have become increasingly costly, but to date little use has been made of alternative materials, such as fiberglass. Fiberglass has sufficient strength for many applications and has the advantage of being light in weight, which reduces shipping costs and makes the material easier to handle. In addition, the members can be fabricated in a large variety of sizes and configurations, short production runs being feasible. Moreover, the amount of fiberglass incorporated in the member and the resulting load-bearing capacity can be varied considerably without changing external dimensions.
One reason that fiberglass members have not come into common use is that it has proven difficult to attach such members to the surrounding structure. It can be equally difficult to attach any components of the member that are not formed by the fiberglass itself.
A primary objective of the present invention is to provide an improved fiberglass structural member which overcomes the attachment difficulties previously associated with this material. A further objective is to provide such a member of increased strength and rigidity.